Grinding machine



J. H. TWOMBLY GRINDING MACHINE Oct. 7, 1952 5 Sheets-Sheet 1 Filed March23, 1951 INVENTOR.

By 144127; aw m Oct. 7, 1952 TWOMBLY 2,612,733

GRINDING MACHINE Filed March 25, 1951 3 Sheets-Sheet 2 INVENTOR BY aww1952 J. H. TWOMBLY 2,612,733

GRINDING MACHINE Filed March 23, 1951 5 Sheets-Sheet 5 IN V EN TOR. BYwflfmfify QM}: gggwwm wires or rods.

the type described, of

' advanced by the threaded rolls.

illustratedin Figures 1 and 2;

Patented Oct. 7, 1952 UNITED STATES PATENT 01: 1.;

- GRINDING MACHINE John Howard 'rwombi niu, Njir'; Florence D. Twomblyexecutrix of said John Howard Twombly, deceased Application March 23,1951, Ser'ia1 No. 217,269 4 Claims. (CL 51' 79) This inventionrelates-to grinding machines and more particularly to machines forperforming' the operation of reducing the diameter of Such machines areused in the production of needles and the like, and also for necking orreducing the diameter through an intermediate portion of the length ofrods or wires, for example tone rods for toy pianos.

A general object of the invention is the provision of a simple,relatively inexpensive, and highly emcient machine for performing anecking operation or a similar grinding operation upon wires or rods ofvarying diameters.

More specifically, it is an object of the invention toprovide a grindingmachine of the type described, comprising a base, a grinding wheel"rotatably supported above said base, a plurality of threaded rollersrotatably supported beneath saidgrinding wheel for successivelyadvancing -a plurality of rods or wires to and beneath thegrinding'wheel, and means for rotating the grinding wheel and thethreaded rolls. Another in a grinding machine of an adjustable supportfor the grinding wheel such that the latter may beadjusted verticallytoward and away from the object is the provision,

base, and 'may also be tilted about an axis parallel to the base andperpendicular to the grinding wheel axis, so as to insure equal grindingaction at either end of thewheel or, alternatively, to adjust the wheelso as to grind points of any desired length'at the ends of the rods orwires.

Another object is the provision, in a machine of the characterdescribed, of a backboard or guard member arrangedparallel and. adjacent"tothe threaded rolls for advancing'the rods or wires, the backboard orguard member serving progress along'th'e threaded rolls,until after theyhave been's'ubjected to the grinding operation.

A further object is the provision, in a machine of the characterdescribed, of means supported adjacent the grinding wheel forfrictionally engaging the wires and rods as they are successivelypresented to the grinding wheel and causing them to rotate about theirown axes as they are Other and further objects, features andadvantageswill be apparent from the description which follows, read inconnection with the accompanying drawings in" which Figure 1 is a frontelevation'of a machine con- "structed in accordance with the presentinvention;

Figure 2 is a plan view of the machine illustrated in Figure 1;

Figure 3 is an end elevation of themachme Figure 4 is a vertical sectionon line 4-4 of Figure 2;

the purpose of preventingthe wires or rods 3 from advancing along theirown axes during their Figure Sis-a vertical section'onlinei -i ofFigure-2; 1 Figure 6-is-a vertical section -on-1ine= 6-6 of Figure 2;

Figure '7 isa vertical sectionon-Jine 'I- l of Figure 3; s

Figure 8 is a horizontal-section online 8-8 of Figure 1;

Figure 9 is a rear perspective view of the upper portion of the machine;

Figure 10 is an enlarged fragmentary sectional view showing theengagement of therods-=being processed with-one of'the threaded rollsfor advancing them, and with the '--frictional member 'for'inducingtheir rotation about'their own-axes; and

- Figure 11 is an elevational view of atone rod for a toy piano,afterpassing'through the machine.

In order toiacilit'a'te an'understanding ofthe invention, reference 'ismade 'to the embodiment thereof shown in the accompanying drawingsanddetailed descriptive languagefisemployed. It will nevertheless beunderstood that no limitation of the invention is thereby intendeda'nd'that various changes and alterations are'conterfipla'ted such as wouldordinarily occur to oneskilled in the art to which the inventionrelates.

Reierring'particularly tUFigures 1 and 2, a machine constructedaccording to "the'inve'ntion comprises generally a base "I ll towhich issecured a horizontal support II and a 'vertical'su'pp'ort l2, the latterbeingsecured to "the'ba'se ln'by means of bolts I3 extendingthroughslo'ts l4 in the base lilso that thesu'pp'o'rt 'l2is-adjustablethereon. The horizontal support ll isprovided at its respective ends'with the twoupstand-;

ing end portions l5 in-whichare journaled a plurality of helicallythreaded'rolls IS, ll" and 18. As best seen in Figure 4', thesaidrbllsarc provided at-one' end with'toothed'pinions i9? 20 and 2|,respectively, meshing 'with intermediate idlers 22 and 23, the pinion-20 being fast-"upon the shaft 24 of roll llgwhichshaftalso carries apulley 25. Means areth'us provided ior rotating the several rolls inunison.- Each ofthe rolls is provided with ahelical thread'bf the same'pitch as-the othersj'wh'ereby'a rod or length of wire laidacross-the-rollsfat rightangles will be advancedjtranslationallyy tliatis to say without alteration 'of its right anglerela'tion' to i therolls.

The rotation-of the rolls l6-l8 -iri--theillus trated embodiment I is Iclockwise looking'; oni the right-hand end of the machine,"which' will"=tend to'advance the rods26 (Figure 2) to the-rightand *would also tendto advance them rearwardly' of themachine, in the direction of theirown:length.

To prevent this'latter movement abackboard or guard 21 is secured alongthe rearward edge of the support H, the guard Tl" terminating at a point28 which is short of the right-hand end of the support ll. After therods have been operated upon by the grinding wheel, and have passed theend of the guard 21, they are permitted to move rearwardly of themachine until they are overbalanced by their own weight and fall oil ofthe threaded rolls into a suitable receptacle.

The vertical support I2 is provided with a dovetailed recess as at 36and a vertically adjustable member 3| is slidably mounted within saidrecess through the medium of bolts 32 extending through slots 33 in thesupport I2 (Figure 9). Adjustment of the member 3| relative to thesupport I2 is obtained through the medium of adjusting screws 34, 35(Figure '7), the screw 34 having threaded engagement with the rearwardlyextending horizontal top portion 36 of the member 3| and having a thrustengagement with the top surface of the support l2. The screw 35 isfreely rotatable in the top portion 33 of member 3|, and has threadedengagement with the support 12. The'screws 34 and 35 thus effect,respectively, a push-and-pull relationship between the member 3| and thesupport I2, for vertical adjustment of the member 3|, which may then befirmly secured in the adjusted relationship by tightening of the bolts32.

A third vertical member 31 is mounted on the vertically adjustablemember 3| by means of a bolt 38 threaded into the member 3! and freelyrotatable in member 3|, so that member 31 is tiltable in a verticalplane about the axis provided by the bolt 38. Adjustment of the tiltingmember 3! is secured by means of screws 39 and ill having threadedengagement with the horizontally projecting flange 4| of the member 3|and bearing upon the upper edge of the tilting member 31. The latter maybe secured in adjusted relationship by tightening the bolt 38 againstcollar 42 which in turn bears on member 3! (Figure 6) The tilting member3'! carries horizontally extending arms 43 at its respective ends, saidarms being formed to provide bearings 44 for the shaft 45 of a grindingwheel 46. A driving pulley 41 is secured on one end of the shaft 45. Onthe outer ends of the respective arms 43, beyond the bearings 44, aresecured short extensions 48 for supporting, through bolts 49, a presserfoot or friction member 59, the vertical relationship of the respectiveends of the latter being adjustable by means of nuts 52 on the bolts 49.The friction member 50 is so adjusted as to engage the upper surfaces ofthe rods or wires 26 as they are successively presented to the grindingwheel 46 and by reason of the friction between the member 50 and therods, to cause the latter to rotate about their own axes as they areadvanced by the threaded rolls, thus causing the rods to be grounduniformly about their axes.

From the foregoing description it is believed that the operation of themachine will be understood without diificulty.

A succession of rods or wires to be operated upon is placed upon therolls l6l8 at the lefthand end of the machine and by rotation of therolls, will be advanced toward the right. As they successively passbeneath the friction member 50 they are engaged by the latter and causedto rotate about their respective axes, meanwhile being engaged by thegrinding wheel 46 rotating about its own axis at right angles to therods. As the rods are advanced past the grinding wheel they are grounduniformly about their axes and,

4 as they are advanced further, past the end 28 of the backboard orguard 21, they are advanced rearwardly of th machine and droppedtherefrom. By reason of the described relationships, the grinding wheelis vertically adjustable with the sliding member 3 I, and its axis maybe tilted in a vertical plane, as desired, by tilting adjustment of themember 3'! relative to the member 3|.

The machine is adapted to the rapid and emcient performance of thedescribed operations, and has a much greater capacity than other knownmachines for performing similar operations.

Having thus described the invention, what is claimed as new and desiredto be obtained by Letters Patent is:

1. Rod grinding machine comprising a base, a vertical support secured onsaid base, a grinding wheel rotatably mounted on said support, aplurality of helically threaded parallel rolls rotatably supported belowsaid grinding wheel and adjacent thereto, for advancing a succession ofrods, disposed crosswise thereof, to and beneath said grinding wheel, astationary friction member supported adjacent said wheel and said rollsfor engaging rods advanced by said rolls and causing the same to rotateabout their axes while passing beneath said wheel, means for rotatingsaid wheel, and means for rotating said rolls.

2. Rod grinding machine comprising a base, a vertical support secured onsaid base, a grinding wheel rotatably mounted on said support, aplurality of helically threaded parallel rolls rotatably supported belowsaid grinding wheel and adjacent thereto, for advancing a succession ofrods, disposed crosswise thereof, to and beneath said grinding wheel,means for rotating said wheel, and means for rotating said rolls, saidvertical support comprising a guideway member secured on said base, avertically adjustable member mounted on said guideway member, and athird member mounted on said vertically adjustable member, said thirdmember including bearings for said grinding wheel.

3. Rod grinding machine as defined in claim 2, said third member beingtiltable about an axis lying parallel to said base and at right anglesto the axis of said bearings.

4. In a rod grinding machine, in combination, a plurality of helicallythreaded parallel rolls, a grinding wheel mounted to rotate above saidrolls on an axis generally parallel to the axes of said rolls, means torotate said rolls and said wheel, and means for causing rods advanced bysaid rolls to rotate about their axes while passing beneath said wheel,said last means comprising a .7 stationary member supported adjacentsaid wheel in position to engage frictionally said rods.

JOHN HOWARD TWOMBLY.

REFERENCES CITED Middlebrook Oct. 22, 1907 Hunt Mar. 11, 1924 FOREIGNPATENTS Country Date Great Britain Sept. 16, 1908 Number Number

